Comparative Study of Silicon Quantum Dot Formation In-situ, Grown with a Gas Mixture of SiH4+N2 and SiH4+NH3

In this study. we investigated the growth mechanism of silicon quantum dots (Si QDs) embedded Tilt Si-nitride hint formed by using plasma-enhanced chemical vapor deposition. Special attention was paid to the influence of the nitrogen source. especially in molecular nitrogen (N-2) and ammonia (NH3). We found that the nitrogen source played a decisive role in determining I he location of nucleation sites of Si QDs. In the case of the SiH4 + NH3 gas source. the Si QDs mainly nucleated at, the surface of the Si substrate; in contrast to the case of SiH4 - N-2 which should no such tendency. We believe that a specific surface reaction of the initially adsorbed NH3 molecules forming low-dimensional structures (NH2-Si-Si-H) on the Si substrate provide the nucleation sites for Si QDs when using a SiH4 + NH3 plasma.